(Reuters) - Microsoft Corp on Thursday announced ethical principles for the use of its facial recognition technology, saying it would bar such technology from being used to engage in unlawful discrimination and would encourage customers to be transparent when deploying such services.

In a blog post on Thursday, Microsoft President Brad Smith pushed for urgency in regulating facial-recognition technology, while adding that tech companies should self regulate too.

"We believe it's important for governments in 2019 to start adopting laws to regulate this technology. The facial recognition genie, so to speak, is just emerging from the bottle," said in a blog post on Thursday.

Identifying faces has become a common feature in consumer products including Apple Inc's iPhone, with Amazon.com Inc and Alphabet Inc's Google offering recognition services as well.

But questions have been raised over the use of such technology.

U.S. civil liberties groups in May called on Amazon to stop offering facial recognition services to governments, warning that the software could be used to target immigrants and people of color unfairly.

Microsoft said in the blog post it will document and communicate the capabilities of the technology, as well as prohibit the use of facial recognition technology to engage in unlawful discrimination.

The other principles listed were fairness, accountability, notice and consent, and lawful surveillance.

Microsoft has also not promised to bar sale of face recognition technology to law enforcement, which is what the American Civil Liberties Union has asked for.

Microsoft said it would formally launch these principles, together with supporting framework, before the end of March 2019, but did not detail how it would implement its new principles.

(Reporting by Ismail Shakil and Siddharth Cavale in Bengaluru; Editing by Shailesh Kuber)